**Problem statement:**
As discussed in this T194139 ticket, deepcat is not enabled on all wikis at the moment. We should inform the user of this potential issue.
**Task description:**
Add warning to the infotext of the deepcat keyword.
{F18098976}
I'm a bit confused because on commons i only find [[https://commons.wikimedia.org/wiki/File:OOjs_UI_icon_alert-warning.svg | this icon ]] but the current OOUI icons use [[https://doc.wikimedia.org/oojs-ui/master/demos/?page=icons&theme=wikimediaui&direction=ltr&platform=desktop#icons-mediawiki-ltr | this alert icon]]. So I guess preferably the latter in orange but if that's not possible in time for the deploy then the one already on commons will do.
The link in [[ https://noc.wikimedia.org/conf/dblists/categories-rdf.dblist | list ]].
**Acceptance criteria:**
[] The warning text appears in the infotext of the deepcat keyword where advanced search is enabled.